It began as a mission to help housewives tired of men leaving toilet seats up, but now a flushless urinal created by 90-year-old Londoner has become a green magic bullet that’s drawing interest from conservationists from Massachusetts to Arizona.

Norm Brooks is no stranger to business success, but the longtime home builder and developer who created much of Kilworth appears on the verge of leaving a wider mark.

At an age when most contemporaries are too frail to work, Brooks has invested more than $100,000 to design, build and manufacture in East London a waterless urinal for homes that’s the only one to gain the approval of plumbing regulators in Canada and the United States.

His urinal is so promising, that even though he hasn’t marketed it, it’s drawn notice at the University of Arizona and heated debate in a Massachusetts town that considered alternatives to a costly sewer system.

“It could become mainstream. I think it’s on the cutting edge,” said Cado Daily, a water resources co-ordinator for a program established by the University of Arizona.

Commercial urinals are a mainstay and flushless versions dominate in water-needy Arizona, but none passed the eye test in homes until Brooks created one that folds closed into a wall, Daily said.

The innovation is not the first by Brooks, who co-founded the home builders’ association and may have been the first here to hire subcontractors to make building more efficient.

When he retired from construction after 54 years in 2005, he turned his focus to what had been the most frequent request to him from housewives: Can you install a urinal?

That he was already in his mid-80s didn’t deter Brooks, who credits training as an engineer for his tendency to seek out better ways of doing things.

“Men are always peeing all over the floor and leaving the toilet seat up,” he said. “I can do something about that.”

Brooks set out to create a urinal that would be certified for homes by those who oversee plumbing codes. His idea was so novel, Canadian authorities wouldn’t test it, so he turned to Americans; the device was later approved for both countries.

Between design, manufacturing and testing, Brooks invested more than $100,000 and got back $11,000 in tax refunds from Canada for research he led from his apartment in a north London retirement home.

But while housewives were the impetus behind his efforts, environmentalists and engineers have shown their enthusiasm.

One engineer estimated London would save more than a million of gallons of water a day if half the homes here used the urinals, Brooks said.

Environmentalists in Falmouth, Mass. pushed for the town to consider requiring urinals rather than spending $50 million in sewers, an effort voters narrowly rejected.

Back in London, Brooks is his own test marketer, installing a urinal in his apartment and making tweaks to make it more user-friendly. Now, he plans a broad marketing effort he hopes will make his flushless urinal, called the Resno, a household name.